1. Geomorphic Context for Sediment Sources, Movement, and Deposition in the Bad River, Bad River Reservation, Wisconsin By Faith Fitzpatrick 1, Kirsten Cahow-Scholtes 2, and Marie Peppler 1 1 USGS Wisconsin Water Science Center and 2 Bad River Tribe FISC, Reno, NV, April 3, 2006

2. Other Clay Loam Peat Sand/gravel Bad River watershed Ontario Minnesota Wisconsin Michigan Lake Superior Apostle Islands Bad River Indian Reservation

3. Problem l The Bad River is the largest sediment source to Lake Superior from the U.S. l Deposition at the mouth has unknown effects on riverine and estuary habitat l Are high sedimentation rates natural? Wisconsin State Historical Society

4. Geomorphic approach for assessing erosion/sedimentation Field--Reach Reach-level geomorphic assessments Valley and channel cross section surveys and coring Helicopter surveys Photo points Longitudinal Profiles Stream network position Modeling Rainfall/runoff Sediment transport Historical Data Streamflow records and rating curves Air photo interpretation General Land Office Surveys 1928 WI Land Economic Inventory Bridge designs Channel alterations Laboratory Sediment texture and organic content Radiometric dating Trace elements Clay mineralogy GIS--Watershed Watershed thematic maps—land cover, soils, geology, elevation, dams Multiple lines of evidence

5. 1860 channel location Section line Transect line Core Valley Cross Section Surveys and Coring photo by M. Peppler

6. White River Marengo River Bad River Tyler Forks Potato River Land Cover

7. Northern Great Lakes Cutover —Late 1800s Photos courtesy Wisconsin State Historical Society

8. White River Marengo River Bad River Tyler Forks Potato River Bad River Reservation Penokee Iron Range Surficial deposits

10. Bad River Marengo River Sandy glacial till, Poorly developed drainage network, no valley Sandy post-glacial shorelines, entrenched valley Clay plain, entrenched/alluvial valley Bedrock outcrop Longitudinal Profiles x

11. June 1946 April 1960 July 1992 Bad River – Annual Peak Flow May 2003

12. Bad River—upstream of the Penokee Range Penokee Iron Range

13. 1930s 2003 1950s Copper Falls, Bad River

14. Cranberry River, WI Landslides Episodic Failure, Long-Term Consequences Bad River Ontonagon River, MI 1975 Landslide Flow direction Flow direction

15. Marengo River—Cross Sections 60-m eroding bluff buried channel Natural levee Pre-settlement soil sand gravel/cobble/boulder glacial deposits

16. 1992 Marengo River—Levee building, May 2003 flood

17. Bad River at USGS streamflow gaging station

18. Bad River at gaging station 1946 1960 2003 1992 1949 1954, 2002 1996, 2001 1916 m. sand loam clay buried soil m./c. sand gravel diamicton AD 1410-1470 BC 110-AD 70 Stage for 10 largest annual peak flows Core 2

19. Low-flow water level Peat Large woody debris Post-European settlement sandy alluvium 0 Meters 1.8 2.7 Bad River – near mouth

20. Preliminary Conclusions l Rates of erosion, transport, and deposition of sediment in the Bad River watershed are elevated above pre-settlement rates. Causes: current and historical land-use practices and more frequent large floods l The main source of sediment is landslides/bluff erosion along main stems and tributaries with entrenched valleys that flow through sandy shoreline deposits related to early Holocene levels of Lake Superior l Erosion, transport, and deposition is dependent on watershed and local geologic setting and position within the drainage network l Post-settlement levee building has been accelerated, resulting in entrenched-looking channels and loss of flood-plain storage

21. Acknowledgments Funding from USGS cooperative study with: Bad River Band of the Lake Superior Chippewa Tribe Technical Assistance: Leah Gibala (Bad River) Ed Kolodjeski (Bad River) Tracy Ledder (Bad River) Jamie Eckholm (Bad River) Dawn Trexel (Bad River) Tom Popowski (USGS) Krista Stensvold (USGS)